Credit

Caption

Coloured scanning electron micrograph (SEM) of Pyramimonas sp., flagellated, scale-covered, marine, green alga. The genus Pyramimonas is a single celled alga that belongs to the group of green algae (Chlorophyta) called prasinophytes. The cell possesses one to many flagella for motility and contains only 1-2 chloroplasts for photosynthesis (not shown in this image). Some species supplement their nutrition by ingesting bacteria and other organic matter, a process called mixotrophy. The cell body is covered with cellulose scales in several layers. These scales can have a complex morphology. Pyramimonas species are abundant in marine plankton and are typically part of the nanoplankton of the sea. Magnification: x3,465 when shortest axis printed at 25 millimetres.